Project Summary/Abstract Substance use disorders (SUDs) among adolescents have risen to epidemic rates in the U.S., with more than half of American adolescents abusing drugs at least once before entering 12th grade. This staggering number of affected youth suffer cognitive and social impairment and increased risk for other dangerous behaviors. Substance use disorders are one of the largest preventable public health challenges in the United States and present costly consequences to the individual, the health care system, and society as a whole, with a large proportion of adults with SUDs reporting drug abuse beginning in adolescence. Opioid use disorders (OUDs) are a particularly dangerous component of youth SUD, resulting in increasing rates of mortality from overdoses; a range of clinical, emotional, and social negative sequelae; and potentially life-changing impacts from impairment during this critical developmental and educational period. In 2014, there were 467,000 adolescents aged 12 to 17 and 978,000 young adults aged 18 to 25 who were non-medical opioid analgesic users in the U.S. Of the intentional adolescent exposures to prescription drugs between 2007 and 2009, 68% were exposures to opioids. Furthermore, many adolescent non-medical users of opioid analgesics later switch to heroin. According to NSDUH data from 2002 to 2011, 79.5% of heroin initiates (52.7% of whom were aged 18 to 25) reported prior non-medical opioid analgesic use. While previous studies have investigated OUD service use and effectiveness in adults, very little is known about how adolescents with OUD are treated or whether these treatments are effective. We propose to use several large, national claims and survey databases to explore factors associated with the incident diagnosis of OUD in adolescents, as well as treatment patterns and outcomes. In addition to exploring patient socio-demographic and clinical characteristics associated with OUD treatment and outcomes, we will also explore family characteristics, such as parental opioid analgesic use. This proposal, responsive to the call for research to ?understand the barriers to successful and sustainable implementation of evidence-based practices and to develop implementation strategies? in the 2016-2020 NIDA Strategic Plan, will address the following aims: 1) Examine geographic variation in, and other factors associated with, incident diagnosis of OUD in adolescents; 2) Examine the patterns of substance abuse treatment in adolescents with incident OUD diagnosis; and 3) Examine the risk of and time to subsequent service use indicative of relapse among adolescents with incident OUD diagnosis. This study would take advantage of a unique set of databases that allows for the investigation of family and clinical characteristics on patterns of opioid use disorder treatment and outcomes in adolescents. By better understanding how adolescents with OUD are treated and how such treatments affect risk of subsequent ED, hospital and detox services, providers, insurers and policymakers will be better able to design developmentally appropriate treatment processes and policies to help mitigate this public health crisis.